1. Nitrogen and Phosphorus Additions Impact Stability of Soil Organic Carbon and Nitrogen in Subtropical Evergreen Broad-Leaved Forest.
- Author
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Huiling Wang, Wang, Jingjing, Teng, Zhen, Fan, Wei, Deng, Pengfei, Wen, Zhenyu, Zhou, Kuang, and Xu, Xiaoniu
- Subjects
ATMOSPHERIC nitrogen ,CARBON in soils ,SOIL dynamics ,FOREST productivity ,FOREST soils ,EVERGREENS ,STABLE isotopes - Abstract
Atmospheric nitrogen (N) deposition can have a series of effects on forest ecosystems. As N deposition increases N availability in forest ecosystems, soil phosphorus (P) becomes a limiting factor for forest productivity. However, it is not clear whether long-term N deposition can affect on soil carbon (C) and N stability, and whether the addition of P can moderate the impact of N deposition. A five-year experiment of N and N + P additions was conducted in a subtropical evergreen broad-leaved forest in eastern China. The seasonal dynamics of soil C and N and the abundance of their stable isotopes (δ
13 C and δ15 N) were investigated in the 0–30 cm layer. Soil C, N and δ13 C and δ15 N abundances had significant vertical distribution characteristics. Soil C and N contents increased significantly under N and N + P additions, especially in the topsoil (0–10 cm); δ13 C did not change significantly under N and N + P additions, but the linear slope (β) between δ13 C and soil organic carbon (SOC) and C/N indicated that N + P addition slowed down the decomposition rate and enhanced the stability of SOC. Soil δ15 N increased significantly under N and N + P additions, and enriched with the increase of seasonal temperature. Our findings implied that the linear slope of δ13 C and SOC (β) and C/N can serve as potential indicators of soil C stability under N and N + P additions in subtropical forests. The soil δ13 C and δ15 N abundance was affected by the interaction between soil C and N. δ13 C abundance showed no significant response of the stability of SOC to N and N + P additions. It suggests that the further study is needed to reveal their response mechanisms to long-term N deposition in subtropical forest ecosystem. [ABSTRACT FROM AUTHOR]- Published
- 2022
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